/****************************************************************
 *
 * Copyright (c) 2010
 *
 * Fraunhofer Institute for Manufacturing Engineering	
 * and Automation (IPA)
 *
 * +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 *
 * Project name: care-o-bot
 * ROS stack name: cob_driver
 * ROS package name: cob_powercube_chain
 * Description:
 *
 * +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 *
 * Author: Felix Geibel, email:Felix.Geibel@gmx.de
 * Supervised by: Alexander Bubeck, email:alexander.bubeck@ipa.fhg.de
 *
 * Date of creation: Aug 2007
 * ToDo:
 *
 * +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the Fraunhofer Institute for Manufacturing 
 *       Engineering and Automation (IPA) nor the names of its
 *       contributors may be used to endorse or promote products derived from
 *       this software without specific prior written permission.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License LGPL as 
 * published by the Free Software Foundation, either version 3 of the 
 * License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License LGPL for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public 
 * License LGPL along with this program. 
 * If not, see <http://www.gnu.org/licenses/>.
 *
 ****************************************************************/
#ifndef _TimeStamp_H
#define _TimeStamp_H

#include <time.h>

//-------------------------------------------------------------------

 
/** Measure system time with very high accuracy.
 * Use this class for measure system time accurately. Under Windows, it uses 
 * QueryPerformanceCounter(), which has a resolution of approx. one micro-second.
 * The difference between two time stamps can be calculated.
 */
class TimeStamp
{
public:
	/// Constructor.
	TimeStamp();

	/// Destructor.
	virtual ~TimeStamp() {};

	/// Makes time measurement.
	void SetNow();

	/// Retrieves time difference in seconds.
	double operator-(const TimeStamp& EarlierTime) const;

	/// Increase the timestamp by TimeS seconds.
	/** @param TimeS must be >0!.
	 */
	void operator+=(double TimeS);

	/// Reduces the timestamp by TimeS seconds.
	/** @param TimeS must be >0!.
	 */
	void operator-=(double TimeS);

	/// Checks if this time is after time "Time".
	bool operator>(const TimeStamp& Time);

	/// Checks if this time is before time "Time".
	bool operator<(const TimeStamp& Time);
	
	/**
	 * Gets seconds and nanoseconds of the timestamp.
	 */
	void getTimeStamp(long& lSeconds, long& lNanoSeconds);

	/**
	 * Sets timestamp from seconds and nanoseconds.
	 */
	void setTimeStamp(const long& lSeconds, const long& lNanoSeconds);
	

protected:

	/// Internal time stamp data.
	timespec m_TimeStamp;
	
private:

	/// Conversion timespec -> double
	static double TimespecToDouble(const ::timespec& LargeInt);

	/// Conversion double -> timespec
	static ::timespec DoubleToTimespec(double TimeS);

};

#endif
